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“Scientists are finally starting to understand the centuries-old mystery of ‘ballooning.'”

From The Atlantic:

Spiders have no wings, but they can take to the air nonetheless. They’ll climb to an exposed point, raise their abdomens to the sky, extrude strands of silk, and float away. This behavior is called ballooning. It might carry spiders away from predators and competitors, or toward new lands with abundant resources. But whatever the reason for it, it’s clearly an effective means of travel. Spiders have been found two-and-a-half miles up in the air, and 1,000 miles out to sea.

It is commonly believed that ballooning works because the silk catches on the wind, dragging the spider with it. But that doesn’t entirely make sense, especially since spiders only balloon during light winds. Spiders don’t shoot silk from their abdomens, and it seems unlikely that such gentle breezes could be strong enough to yank the threads out — let alone to carry the largest species aloft, or to generate the high accelerations of arachnid takeoff. Darwin himself found the rapidity of the spiders’ flight to be “quite unaccountable” and its cause to be “inexplicable.”

But Erica Morley and Daniel Robert have an explanation. The duo, who work at the University of Bristol, has shown that spiders can sense the Earth’s electric field, and use it to launch themselves into the air.

Every day, around 40,000 thunderstorms crackle around the world, collectively turning Earth’s atmosphere into a giant electrical circuit. The upper reaches of the atmosphere have a positive charge, and the planet’s surface has a negative one. Even on sunny days with cloudless skies, the air carries a voltage of around 100 volts for every meter above the ground. In foggy or stormy conditions, that gradient might increase to tens of thousands of volts per meter.

Ballooning spiders operate within this planetary electric field. When their silk leaves their bodies, it typically picks up a negative charge. This repels the similar negative charges on the surfaces on which the spiders sit, creating enough force to lift them into the air. And spiders can increase those forces by climbing onto twigs, leaves, or blades of grass. Plants, being earthed, have the same negative charge as the ground that they grow upon, but they protrude into the positively charged air. This creates substantial electric fields between the air around them and the tips of their leaves and branches — and the spiders ballooning from those tips.

Nick Fox: “I think we had a stroke of luck here that the lions got to them before they got to the rhinos.”

From CBS News:

In a stunning instance of the animal kingdom taking karma into its own hands — or rather, paws — at least three poachers were mauled to death and then eaten by lions earlier this week after they illegally entered the Sibuya Game Reserve in South Africa to hunt rhinos.

“They strayed into a pride of lions — it’s a big pride so they didn’t have too much time,” Sibuya Game Reserve’s owner, Nick Fox, told AFP Thursday. “We’re not sure how many there were — there’s not much left of them.

He added, however, that the clothing strewn around the scene points to there being at least three. Authorities believe the men entered the game reserve in the early hours of Monday; they were found dismembered the following day, the news agency reports.

In Africa, there are fewer than 25,000 rhinoceros left in the wild due to a boom in demand for their horns, which are sold on the black market in Asia for their supposed medicinal qualities. In fact, in South African parks and game reserves, these majestic, tank-like creatures are under daily assault. A May 2018 “60 Minutes” report revealed that they are being slaughtered at the shocking rate of three a day at the hands of poachers like the group killed in Sibuya.

A heartwarming story that would have been heartbreaking, but for the good ending.

From the Guardian:

A daredevil raccoon that became an online sensation when it spent almost 20 nail-biting hours scaling a 25-storey office tower in Minnesota has been safely rescued and released back into the wild after making it to the top of the building unscathed.

The animal’s ascent on the outside of the UBS building in downtown St Paul city was watched across the world on social media on Tuesday, with updates on its progress posted regularly by the Minnesota Public Radio under the hashtag #MPRraccoon. Crowds also gathered at the scene to watch.

Despite widespread concern for its safety – as well as Spider-Man and Mission Impossible jokes – it reportedly reached the roof at 3am local time yesterday, where cat food was waiting inside a humane trap.